This invention is related an automatic sampling device and in particular to a device that automatically loads and unloads samples from laboratory analyzing equipment.
A differential scanning calorimeter (DSC) is widely used for thermoanalytical analysis. The DSC is used for research and quality control and measures both the temperature and heats associated with various transitions in materials such as boiling points and melting points, liquid crystal transitions, heats of reaction, specific heat capacity, oxidative and thermal stability, purity, polymer cure, glass transition and reaction kinetics. Performing specific experiments with the DSC is time consuming and repetitive for an operator. Typical thermal analysis equipment is shown in Harden et al U.S. Pat. No. 3,283,560 issued Nov. 8, 1966 and in Johnson U.S. Pat. No. 4,350,446 issued Sept. 21, 1982. There is a need for a device that will automatically load and unload a series of samples from equipment such as a DSC and allow for the unattended operation of such equipment.
The prior art shows automated devices that can be used for repetitive operations such as Inaba et al U.S. Pat. No. 4,274,802 issued June 23, 1981, Hutchins et al U.S. Pat. No. 4,488,241 issued Dec. 11, 1984 Hutchins et al. U.S. Pat. No. 4,510,684 issued Apr. 16, 1985 and Hutchins et al U.S. Pat. No. 4,507,684 issued Mar. 26, 1985. However, for a device to be useful, it must be programmable with equipment such as the DSC, be able to load a sample for analysis, allow the DSC to perform any of its preprogrammed analytical tasks, then unload the sample and must be able to perform the above tasks repetitively. Also, special gripper devices are required to handle the sample containers and reference containers and covers used. One prior art gripper device is shown Ionescu U.S. Pat. No. 4,509,783 issued Apr. 9, 1985 but cannot be controlled at the accuracy required to handle sample and reference containers. Many other prior art devices use vacuum for holding samples which is not workable for covered and uncovered sample containers used with analytical equipment such as a DSC or dual cell DSC.
The autosampler of this invention provides robotic means for automated and computer programmed loading and unloading of a plurality of samples to and from equipment such as a DSC to allow for automated and unattended analysis of these samples.